Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754819AbZA1D7A (ORCPT ); Tue, 27 Jan 2009 22:59:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754479AbZA1D6m (ORCPT ); Tue, 27 Jan 2009 22:58:42 -0500 Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:36901 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754278AbZA1D6k (ORCPT ); Tue, 27 Jan 2009 22:58:40 -0500 Message-ID: <497FD62D.7090003@jp.fujitsu.com> Date: Wed, 28 Jan 2009 12:51:09 +0900 From: Yasuaki Ishimatsu User-Agent: Thunderbird 1.5.0.12 (X11/20071019) MIME-Version: 1.0 To: mingo@elte.hu, linux-kernel@vger.kernel.org Subject: [PATCH take2 1/3] fix debug message of CPU clock speed References: <497FD4F3.3080006@jp.fujitsu.com> In-Reply-To: <497FD4F3.3080006@jp.fujitsu.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5111 Lines: 139 LOCAL APIC is corrected by PM-Timer, when SMI occurred while LOCAL APIC is calibrated. In this case, LOCAL APIC debug message(Boot with apic=debug) is displayed correctly, however, CPU clock speed debug message is displayed wrongly . When SMI occured on my machine, which has 1.6GHz CPU, CPU clock speed is displayed 3622.0205 MHz as follow. CPU0: Intel(R) Xeon(R) CPU 5110 @ 1.60GHz stepping 06 Using local APIC timer interrupts. calibrating APIC timer ... ... lapic delta = 3773130 ... PM timer delta = 812434 APIC calibration not consistent with PM Timer: 226ms instead of 100ms APIC delta adjusted to PM-Timer: 1662420 (3773130) ..... delta 1662420 ..... mult: 71411249 ..... calibration result: 265987 ..... CPU clock speed is 3622.0205 MHz. =====> here ..... host bus clock speed is 265.0987 MHz. This patch fixes to displaying CPU clock speed correctly as follow. CPU0: Intel(R) Xeon(R) CPU 5110 @ 1.60GHz stepping 06 Using local APIC timer interrupts. calibrating APIC timer ... ... lapic delta = 3773131 ... PM timer delta = 812434 APIC calibration not consistent with PM Timer: 226ms instead of 100ms APIC delta adjusted to PM-Timer: 1662420 (3773131) TSC delta adjusted to PM-Timer: 159592409 (362220564) ..... delta 1662420 ..... mult: 71411249 ..... calibration result: 265987 ..... CPU clock speed is 1595.0924 MHz. ..... host bus clock speed is 265.0987 MHz. Signed-off-by: Yasuaki Ishimatsu --- arch/x86/kernel/apic.c | 47 ++++++++++++++++++++++++++++++----------------- 1 file changed, 30 insertions(+), 17 deletions(-) Index: linux-2.6.29-rc2/arch/x86/kernel/apic.c =================================================================== --- linux-2.6.29-rc2.orig/arch/x86/kernel/apic.c 2009-01-28 12:14:39.000000000 +0900 +++ linux-2.6.29-rc2/arch/x86/kernel/apic.c 2009-01-28 12:14:42.000000000 +0900 @@ -535,7 +535,8 @@ static void __init lapic_cal_handler(str } } -static int __init calibrate_by_pmtimer(long deltapm, long *delta) +static int __init +calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc) { const long pm_100ms = PMTMR_TICKS_PER_SEC / 10; const long pm_thresh = pm_100ms / 100; @@ -557,18 +558,29 @@ static int __init calibrate_by_pmtimer(l if (deltapm > (pm_100ms - pm_thresh) && deltapm < (pm_100ms + pm_thresh)) { apic_printk(APIC_VERBOSE, "... PM timer result ok\n"); - } else { - res = (((u64)deltapm) * mult) >> 22; - do_div(res, 1000000); - pr_warning("APIC calibration not consistent " - "with PM Timer: %ldms instead of 100ms\n", - (long)res); - /* Correct the lapic counter value */ - res = (((u64)(*delta)) * pm_100ms); + return 0; + } + + res = (((u64)deltapm) * mult) >> 22; + do_div(res, 1000000); + pr_warning("APIC calibration not consistent " + "with PM Timer: %ldms instead of 100ms\n",(long)res); + + /* Correct the lapic counter value */ + res = (((u64)(*delta)) * pm_100ms); + do_div(res, deltapm); + pr_info("APIC delta adjusted to PM-Timer: " + "%lu (%ld)\n", (unsigned long)res, *delta); + *delta = (long)res; + + /* Correct the tsc counter value */ + if (cpu_has_tsc) { + res = (((u64)(*deltatsc)) * pm_100ms); do_div(res, deltapm); - pr_info("APIC delta adjusted to PM-Timer: " - "%lu (%ld)\n", (unsigned long)res, *delta); - *delta = (long)res; + apic_printk(APIC_VERBOSE, "TSC delta adjusted to " + "PM-Timer: %lu (%ld) \n", + (unsigned long)res, *deltatsc); + *deltatsc = (long)res; } return 0; @@ -579,7 +591,7 @@ static int __init calibrate_APIC_clock(v struct clock_event_device *levt = &__get_cpu_var(lapic_events); void (*real_handler)(struct clock_event_device *dev); unsigned long deltaj; - long delta; + long delta, deltatsc; int pm_referenced = 0; local_irq_disable(); @@ -609,9 +621,11 @@ static int __init calibrate_APIC_clock(v delta = lapic_cal_t1 - lapic_cal_t2; apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta); + deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1); + /* we trust the PM based calibration if possible */ pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1, - &delta); + &delta, &deltatsc); /* Calculate the scaled math multiplication factor */ lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS, @@ -629,11 +643,10 @@ static int __init calibrate_APIC_clock(v calibration_result); if (cpu_has_tsc) { - delta = (long)(lapic_cal_tsc2 - lapic_cal_tsc1); apic_printk(APIC_VERBOSE, "..... CPU clock speed is " "%ld.%04ld MHz.\n", - (delta / LAPIC_CAL_LOOPS) / (1000000 / HZ), - (delta / LAPIC_CAL_LOOPS) % (1000000 / HZ)); + (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ), + (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ)); } apic_printk(APIC_VERBOSE, "..... host bus clock speed is " -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/